DE 199 23 889 C2 (corresponding to U.S. Pat. No. 6,481,793 B1) describes a vehicle seat protection cover made of double-layered plastic film, that is, a front layer and a back layer, according to DE 41 32 714 C1. In this vehicle seat protection cover, the two portions of the back layer forming pockets are connected by connection strips which extend over the free edges of the portions forming the pockets along transverse welds. The connection strips are also connected to the front layer, so that the back layer (that therefore is substantially continuous) comprises an opening with a closed boundary. The front layer and the back layer therefore comprise contours of the same size and are connected with each other continuously on all four edges, that is, in the region of the transverse welds as well as in the region of the longitudinal edges. The front layer is realized as continuously closed. In the back layer the opening with the closed edge is provided. On all sides the opening is arranged with a distance to the contour of the vehicle seat protection cover when lying flat. The opening constitutes the only opening by the aid of which the vehicle seat protection cover can be put over the backrest and the seat cushion. In addition to the two pockets known until now, by the connection strips additional transverse pockets connecting the pockets are produced. The transverse pockets reach behind the seat cushion and the backrest in transition regions and therefore pose an effective protection of these endangered parts of the vehicle seat against soiling. The danger of sliding in use of the vehicle seat which is protected by the vehicle seat protection cover is practically eliminated. Still, in the manufacture of this vehicle seat protection cover all manual work is avoided. An additional use of rubber bands, film strips and similar is also dispensed with and an additional mounting effort becomes unnecessary. In putting the vehicle seat protection cover over the vehicle seat, the vehicle seat protection cover rather automatically reaches its protection position enwrapping the seat cushion and the backrest. Via the transverse weld, the front layer is continuously connected to the back layer on every seat. On the other hand, the transverse welding can be produced in such a way that in this production step at the same time the separate vehicle seat protection covers are separated from each other so that they can be laid into a stack layered one above the other and in this way can also be shipped to a manufacturer of the vehicle seat, to a vehicle manufacturer or to a garage. Besides that, it is also possible to let the separate vehicle seat protection covers remain adhering to one another via perforations and to wrap such an infinity sheet onto a supply roll. An undesired loosening or dropping of the vehicle seat protection cover from the vehicle seat is to be avoided by using as a part separate from the vehicle seat protection cover a rubber band which after putting the vehicle seat protection cover over the vehicle seat is passed over the backrest as a closed loop in such a way that the rubber band is snug in the transition region between seat cushion and backrest. At the same time, the front layer of the seat cover in the transition region between seat cushion and backrest is fixed by the rubber band so that a danger of sliding is countered. Alternatively it is suggested that e.g. in the center portion of the free edge of the pocket which encloses the backrest two film strips are welded to the vehicle seat protection cover. The two film strips can then be slung to the front after the vehicle seat protection cover has been put over the vehicle seat and knotted with each other there. In this way a closer fit of the front layer of the seat cover can be guaranteed in the transition region between the seat cushion and the backrest.
According to DE 199 23 889 C2, a further known vehicle seat protection cover is at first manufactured as this is described in DE 1 630 878 B. After the parting of a plastic sheet into the separate vehicle seat protection covers, there is a welding of a semi-tube along the free edges of the pockets formed by the back layer and along the free edges of the front layer in the portion not covered by the pockets. During this welding of the semi-tube, a rubber band in the form of a loop is inserted. Then, with this rubber band an opening is made on the vehicle seat protection cover. The opening is used for putting the vehicle seat protection cover over the vehicle seat. The rubber band then exerts a certain tightening effect, so that especially the front layer of the vehicle seat protection cover is held closer to the seat cushion and the backrest. Due to the welding of the semi-tube with the rubber band (which is done by hand), such a vehicle seat protection cover is especially effort-consuming and expensive, but on the other hand has a good protective effect. Putting such a vehicle seat protection cover over a vehicle seat, however, is comparatively more difficult to be done than with the vehicle seat protection cover described before.
DE 199 23 889 C2 also describes it as known to sew a rubber band onto the edge of an opening of a seat cover made of a plastic film, said opening having a closed boundary. The sewing is done by hand and while fixing the rubber band with a pre-tension. This results in the rubber band as an elastic foreign object pulling together the inelastic film while forming folds. This is not only optically disrupting but also makes the winding onto a roll impossible. Even as individual items in the stack, such vehicle seat protection covers can only be handled with difficulty. Further disadvantages of this embodiment are a puckered fit on the vehicle seat, a liability of interference with electronic barriers and a danger of tearing and of propagation of tears of the film.
Finally, DE 199 23 889 C2 also describes as known a vehicle seat protection cover for vehicle seats according to DE 1 920 529 A which consists of an underyarn cloth that is elastically stretchable in all directions with a high elastic recovery and with high-pile wool or a similar material knitted into it in a stretched state of the elastic yarn cloth. Due to the high elasticity, such a vehicle seat protection cover is simple in handling and can be easily applied to the vehicle seat. The vehicle seat protection cover can be realized as a universal vehicle seat protection cover which can adapt to vehicle seats of different geometry. The vehicle seat protection cover in this case can consist of several parts or layers where in one of the layers an opening is provided to enable pulling the vehicle seat protection cover over the backrest as well as over the seat cushion.
On this background, DE 199 23 889 C2 suggests to manufacture at least the back layer of the vehicle seat protection cover wholly or partially from an elastic, resilient plastic film. The elasticity of the back layer is to be used to enable the removal and reinstallation of the vehicle seat protection cover, especially in connection with the mounting of the vehicle seat, to guarantee the reachability of mounting screws of the vehicle seat, for the installation of a drawer, a fire extinguisher and similar. Due to the elasticity, the vehicle seat protection cover can be manufactured slightly smaller in its dimensions than before. The elasticity still provides for a simple handling in putting the vehicle seat protection cover over the vehicle seat and an improved fit of the vehicle seat protection cover. Furthermore, the vehicle seat protection cover in the state put over the vehicle seat lies snug against to the contour of the vehicle seat. In this way, a possibility of interference disappears, for example when the correct position of the vehicle seat in the vehicle is measured and checked with electronic barriers. Overhanging parts of the film or folds of the vehicle seat protection cover can no longer lead to an interference. The vehicle seat protection cover can quickly and securely as well as fold-free be pulled on with a fit that is snug to the contours of the vehicle seat. Preferably, equipping the plastic film forming the back layer with an elastic elongation of 50% (preferably at least 60%) is suggested. As a material for the film material of the back layer a copolymer is used, especially made of ethylene vinyl acetate or butylene vinyl acetate, where other materials can also conform to the requirements, for example a thermoplastic elastomer or an especially elastic low-density material which may be used at least in layers or in blends or at 100%. It is additionally suggested that the elastic back layer can be equipped with a multi-layer film, where one layer of the multi-layer film is purposely equipped with good welding characteristics. It is furthermore suggested that the plastic film forming the front layer on the inner side turned towards the vehicle seat can be realized as anti-slip and on the outer side be realized as smooth and slick.
DE 297 05 666 U1 suggests a vehicle seat protection cover made of a fiber fleece which is said to have a pleasant textile surface characteristic, to form no pilling, to have a good fit to the respective form of the vehicle seat and to be able to be recycled after use if possible for the same use. In order to achieve this, the vehicle seat protection cover according to DE 297 05 666 U1 is manufactured of a fiber fleece the mass per unit area of which is smaller than 100 g/m2. The fiber fleece, in order to achieve this, is cut to the shape of the vehicle seat protection cover. The vehicle seat protection cover formed in this way and which is generally in one part then fully covers the seat area, the seat edges and the backrest. To guarantee the continuous fit and the sticking on all sides of the vehicle seat protection cover, together with the tailored cut of the vehicle seat protection cover two holding elements are active. These are on the one hand a rubber band sewn to the seat fold or a textile band sewn to the gathered fiber fleece or a sewn tie with a one-sided loop as well as on the other hand a further mechanical connection between a holding flap sewn to the back seat part of the vehicle seat protection cover and the back part of the backrest of the vehicle seat protection cover. After use of this vehicle seat protection cover it is to be shredded coarsely. In a tearing machine, then torn fibers are manufactured which can be mixed back into a fiber fleece.
Further prior art which concerns protective covers for vehicle seats or child seats (that can be used for a long time, are comparatively massive and individually pre-formed and washable) is known from documents WO 2008/002684 A2, U.S. Pat. No. 7,537,284 B1, US 2005/130537 A1 and U.S. Pat. No. 5,806,925 A.
The patent document EP 2 913 224 B1 proposes a vehicle seat protection cover in which a back layer (at least partially) consists of a plastic film, while a front layer (at least partially) consists of a fleece. The back layer is realized as elastic. This realization is based on the idea to adapt the front layer on the one hand and the back layer on the other hand specially to their respective demands: The front layer formed with the fleece provides a pleasant contact surface for the user. The front layer is breathable in the region of the fleece, which on the one hand is advantageous for the wicking away of sweat and on the other hand for the wicking away of residual humidity evaporating from the vehicle seat. A significantly improved sound emission characteristic of the fleece at movements of the user on the vehicle seat can also be used. On the other hand, even with a non-transparent front layer made of a fleece, the back layer made of plastic can remain transparent so that the vehicle seat remains visible through the vehicle seat protection cover. Finally, the elasticity of the back layer can be used to guarantee a close fit of the vehicle seat protection cover, good mounting ability and demounting ability of the vehicle seat protection cover and possibly also an option for repeated use of the vehicle seat protection cover. In the fleece, fibers of polyethylene, PET, polyamide and/or polypropylene can be used. The plastic layer in the region of the back layer can be formed with one or multiple layers with manufacture of the plastic film with a laminating or co-extruding. EP 2 913 224 B1 proposes not to sew the front layer made of the fleece and the back layer made of the plastic film together, but rather to weld them together. In order to do this, the fleece can have concave bulges in the region of which the fleece is compacted. In thickened regions remote from these concave bulges the welding of the fleece to the plastic film can be done. For welding, a thermotransfer method, a heating wire or another heating element (possibly with a pressing of the heated surfaces to be welded under pressure) can be used.
In the non-prepublished European patent application with the official file number EP 16 155 462.1 (cp. the parallel non-prepublished corresponding U.S. Ser. No. 15/428,559), prior art according to the internet addresses
http://www.slipngrip.com/SlipNGrip_Seat_Covers/FG-P9943-SC.html
http://www.gammaplast.com/public/download/scheda_1_coprisedili_001.pdf
is described which concerns vehicle seat protective films used as a kind of throw cover, which can in a simplified way be described as coat-like. These vehicle seat protection covers are formed with an upper tube part which is realised as closed in the circumferential direction and is closed in the upwards direction in the region of the upper edge, in which way the tube part forms an upper pocket that in cross section has closed edges. A lower tube part attaches directly to this upper tube part which on the back side comprises a slit that is continuous in a longitudinal direction and which is not closed in the upwards direction in the transition region to the upper tube part as well as in the downwards direction in the region of a lower edge. While opening the slit in the lower tube part, the vehicle seat protection cover can be thrown over a vehicle seat, where the upper pocket with the closed boundaries formed by the upper tube part can be pulled onto a headrest and the upper end portion of the backrest. The upper pocket here has to have a cross section which is at least as large as the cross section of the backrest in the upper end portion of the same. The opened lower tube part covers the lower part of the backrest as well as the seat area, where the lower tube part can overhang the seat cushion to the sides. To avoid a tearing of the vehicle seat protection cover in the transition region from the slit of the lower tube part to the upper tube part, the end portion of the slit of the lower tube part in the transition region to the upper tube part can be reinforced with a reinforcing film that is adhesively attached.
The patent application EP 16 155 462.1 on this background suggests a vehicle seat protection film which is manufactured of a plastic film with a thickness of less than 80 μm. An upper tube part which is not closed in the circumferential direction and which therefore has open boundaries, at most is used for pulling over a headrest of the vehicle seat, while the lower tube part equipped with a slit extends over the entire seat area formed by the seat cushion and the backrest and which is realised with a slit here. Preferably, no upper tube part is present at all so that the slit of the vehicle seat protection film is continuous to the closed upper edge of the vehicle seat protection film, especially a welding in the region of the upper edge. In this way, the complete upper pocket, too, is realised with an open boundary in cross section. Back layer parts separated from each other by the slit can be arranged as overlapping, in which way in the region of a weld seam in order to provide an upper edge three layers can be welded together. The vehicle seat protection film can consist of a one-piece plastic film which can also be realised as a multi-layer film. It is possible that the lateral extension of a front layer is smaller than the lateral extension of a backrest of a vehicle seat or even corresponds to approximately half the circumference of the headrest in the upper end portion of the headrest or is smaller than this. This embodiment is based on the finding that due to the slit of the back layer the cross section of the vehicle seat protection film can be opened so far that the vehicle seat protection film can be put over a backrest with a larger cross section (with a conical tapering in the direction of the upper edge at a sufficient distance from the upper edge). Such a vehicle seat protection film can therefore also be used for different vehicle seat types with different dimensions.
Further prior art is known from DE 690 22 404 T2 (corresponding to U.S. Pat. No. 6,048,026 A) and JP H08 38313 A.